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Adventitious shoot regeneration from the petioles of European plum ‘Tardicots’ (Prunus domestica) was studied in this study. The influences of different concentrations of thidiazuron (TDZ) and 2,4-Dichlorophenoxyacetic acid (2,4-D), dark culture period, and different basal salts on shoot regeneration were evaluated. Woody plant medium (WPM) was the best basal medium for the European plum initial culture, supplemented with 2.0 mg L−1 thidiazuron (TDZ) and 0.2 mg L−1 2,4-D. The explants, which were maintained in darkness for 14 d, as a result had the highest regeneration rate (83.33%). The regenerated shoots were subcultured at 4 weeks intervals. Addition of IBA (1.0 mg L−1) in the rooting medium produced the highest roots (93.3%) when maintained in dark for 7 d.

The diffusion coefficients of lithium ions ( D Li + ) in nano-Si were determined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic intermittent titration technique (GITT). D Li + values are estimated to be ~ 10 − 12 cm 2 s − 1 and exhibit a “W” type varying with the lithium concentration in silicon. Two minimum regions of D Li + (at Li 2.1 ± 0.2 Si and Li 3.2 ± 0.2 Si) are found, which probably result from two amorphous compositions (a-Li 7 Si 3 and a-Li 13 Si 4 ). Besides the two minimum regions, one maximum D Li + is observed at Li 15 Si 4 , corresponding to the crystallization of highly lithiated amorphous Li x Si.

The influence of cryogenic deformation on Bi2223 superconducting tapes has been investigated in this paper. Mechanical deformation was carried out on Ag-sheathed mono- and multi- filamentary tapes and silver alloy-sheathed multi- filamentary tapes at liquid nitrogen temperature (77 K) and room temperature, respectively. Results show that the critical current of the Bi2223 tapes is significantly enhanced by cryogenic deformation. SEM microstructure observations show that the cryogenic-tapes have higher core density, smoother silver/superconductor interface, and better grain alignment. Tensile tests indicate that the tapes pressed at liquid nitrogen temperature have better tensile behavior than those pressed at room temperature.

The mechanical relaxation spectra of a superconducting and a non-superconducting MgCNi3 samples were measured from liquid nitrogen temperature to room temperature at frequency of kilohertz. There are two internal friction peaks (at 300 K labeled as P1 and 125 K as P2) for the superconducting sample. For the non-superconducting one, the position of P1 shifts to 250 K, while P2 is almost completely depressed. It is found that the peak position of P2 shifts towards higher temperature under higher measuring frequency. The calculated activation energy is 0.13eV. We propose an explanation relating P2 to the carbon atom jumping among the off-center positions. And further we expect that the behaviors of carbon atoms maybe correspond to the normal state crossovers around 150 K and 50 K observed by many other experiments.

The design of state functional observer and state feedback for systems with input time delays is addressed using the factorization approach in the frequency domain. The design needs to achieve the loop transfer recovery of direct state feedback by using the functional observer-based feedback control. A necessary and sufficient condition is given for the existence of the state functional observers for such systems. A parametrization for all observers of time-delay systems is proposed. Based on the results of the parametrization, the state functional observer and state feedback design procedure is presented. The computation can be implemented in state-space form using standard algorithms. Design examples are given to illustrate the procedure.

Using resistivity, heat-capacity, thermal-expansion, and susceptibility measurements we study the normal-state behavior of KFe2As2. We find that both the Sommerfeld coefficient gamma = 103 mJ mol-1 K-2 and the Pauli susceptibility chi = 4x10-4 are strongly enhanced, which confirm the existence of heavy quasiparticles inferred from previous de Haas-van Alphen and ARPES experiments. We discuss this large enhancement using a Gutzwiller slave-boson mean-field calculation, which reveals the proximity of KFe2As2 to an orbital-selective Mott transition. The temperature dependence of the magnetic susceptibility and the thermal expansion provide strong experimental evidence for the existence of a coherence-incoherence crossover, similar to what is found in heavy fermion and ruthenate compounds, due to Hund's coupling between orbitals.

Using resistivity, heat-capacity, thermal-expansion, and susceptibility measurements we study the normal-state behavior of KFe2As2. Both the Sommerfeld coefficient (γ≈103 mJ mol(-1) K(-2)) and the Pauli susceptibility (χ≈4×10(-4)) are strongly enhanced, which confirm the existence of heavy quasiparticles inferred from previous de Haas-van Alphen and angle-resolved photoemission spectroscopy experiments. We discuss this large enhancement using a Gutzwiller slave-boson mean-field calculation, which shows the proximity of KFe2As2 to an orbital-selective Mott transition. The temperature dependence of the magnetic susceptibility and the thermal expansion provide strong experimental evidence for the existence of a coherence-incoherence crossover, similar to what is found in heavy fermion and ruthenate compounds, due to Hund's coupling between orbitals.

A novel method is presented to determine the dynamic characteristics of a multi-DOF rigid body structure from vibration measurements and coordinates of the transducers. These characteristics include the center of gravity, moment of inertia, and mass; stiffness, center of stiffness and moment of stiffness; damping, center of damping and moment of damping; and corresponding principal values and axes. The method is capable of handling complicated structures with various DOFs, from 2 up to maximum 6. The mass modified matrices M−1K and M−1C (or mass M, stiffness K, and damping C matrices) are first obtained based on measured vibration data and estimated rigid-body modes by Data Dependent Systems (DDS) methodology, which is accurate even for highly damped structures. Relationships between the physical characteristics and the mass modified matrices have been derived to solve the dynamic properties. The properties of up to 5 individual spring and dashpot supports can be determined by solving linear simultaneous equations. New concepts about the center of stiffness, moment of stiffness, center of damping, and moment of damping and the estimation method are presented. An example, using a simple structure, demonstrated the capability of the proposed method.

The effects of nitric oxide (NO) donor sodium nitroprusside (SNP) on the proliferation and apoptosis and on Bcl-2, Bax and p53 proteins of pulmonary fibroblasts were investigated by using MTT cleavage assay, agarose gel electrophoresis and flow cytometric analysis. The results showed increases in the optical density (550 nm) of MTT cleavage assay, the number of cells and the proliferation index (PI), in comparison with the control. The number of apoptotic cells was also increased, though the percentage of apoptotic cells was too low to reveal oligonucleosomal fragmentation of characteristic ladder pattern, which is associated with apoptosis. In the meantime, the level of Bcl-2 decreased and that of Bax increased, while the p53 remained unchanged. These results suggest that exogenous NO has a dual effect on proliferation and apoptosis; and the action of NO on pulmonary fibroblasts is mainly proliferative. Down regulation of Bcl-2 and up regulation of Bax are implicated in the molecular mechanisms of this action.

We report a collection of lowest-energy structures of hydrocarbon molecules C n H m (n = 6-18, m = 0 - 2n + 2) within the wide hydrogen chemical potential range. The genetic algorithm combined with Brenner's empirical potential is applied for the search. The resultant low-energy structures are further examined by ab initio quantum chemical calculations. The lowest-energy molecules with several additional low-energy structures are classified to four groups according to their structural motifs and the phase diagram with respect to carbon atom number and hydrogen chemical potential is presented. The results provide useful information for identifying the hydrocarbon molecules in the interstellar medium as well as addressing the hydrocarbon-related nanofragment growth in experiments.

Ab initio molecular dynamics simulations are performed to study the liquid and undercooled liquid of zirconium. Local structure orders in the liquid at temperatures from 2500 K down to 1830 K are analyzed by using the recently developed cluster alignment method. Our study clearly shows the presence of body-centered-cube (BCC) short-range order in the undercooled liquid in addition to icosahedral order. A strong fluctuation and competition between the short-range icosahedra and BCC orders in the undercooled liquid at 1830 K are also demonstrated from the cluster alignment scheme.

A quantum-mechanical method for estimating the cation distribution in spinel ferrites is proposed, by which the ionization energy of the cations and the Pauli repulsion energy is considered, together with the magnetic ordered energy and the tendency toward charge density balance. Using this method, not only can the difference between the observed and the traditional theoretical magnetic moments of the spinel structure ferrites MFe2O4 (M=Mn,Fe,Co,Ni,Cu) be explained, but also the dependence of the magnetic moments of the ferrites M1−xZnxFe2O4 (M=Mn,Fe,Co,Ni,Cu) on the doping level x can be fitted.